1. Field of the Invention
This invention relates to a voltage indicator for the battery in a camera.
2. Description of the Prior Art
It is known in the prior art to provide a battery checker in such form that the battery voltage is converted to the corresponding frequency of pulses by which the indicating means, such as an LED, is driven to light on an off, thereby the battery voltage is indicated by the lighting-on and lighting-off period. However, this method, because it uses the direct V-f conversion of the battery voltage which varies the lighting-on and lighting-off period linearly with the battery voltage, cannot clearly indicate a fine variation of the battery voltage. To solve this problem, use may be made of, for example, an analog expanding circuit so that the battery voltage, after having been expanded, is subjected to the V-f conversion with the advantage that the range of variation of the lighting-on and lighting-off period for the fine variation of the battery voltage is increased. However, this alternate method has a disadvantage, which arises from the use of such analog expanding circuit that the expanding characteristics of the circuit components necessary to analogically expand the battery voltage itself are largely influenced by temperature and therefore the expanding operation cannot be performed with high precision.